A pc composite material and a method for preparing the same

Abstract

The application discloses a PC composite material and a preparation method thereof, and belongs to the technical field of polymer materials. The material is prepared by introducing SAN resin and ASA resin with specific molecular weight into a base PC resin, and the acrylonitrile content in the ASA resin is specially limited, so that the product can guarantee good weather resistance and deformation resistance, and meanwhile, the easy processability of the PC resin itself can be retained.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a PC composite material and its preparation method. Background Technology

[0002] PC / ASA alloy is a polymer alloy material that combines the weather resistance, chemical stability, and easy processing of ASA (styrene-acrylonitrile-acrylate terpolymer) with the mechanical strength and temperature resistance of PC (polycarbonate), and is theoretically very suitable for the manufacture of automotive parts.

[0003] However, PC / ASA alloy materials lack mechanical aging resistance and deformation resistance, especially when used in automotive air intake grille components. If the expected weather resistance, deformation resistance, and dimensional stability cannot be achieved, the component will undergo severe deformation after a period of use, affecting not only intake efficiency but also potentially causing safety issues. Although existing technologies introduce materials such as polyacrylates or PMMA-based copolymers to improve the weather resistance of products, the deformation resistance of these products still fails to meet the usage requirements. Furthermore, the processability of the product is also affected due to the introduction of these materials. Summary of the Invention

[0004] Based on the deficiencies of existing technologies, the present invention aims to provide a PC composite material. This material introduces SAN (styrene-acrylonitrile copolymer) resin and ASA resin of specific molecular weights into the PC matrix resin, and specifically limits the acrylonitrile content in the ASA resin. This not only ensures good weather resistance and deformation resistance, but also retains the easy processability of the PC resin itself.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A PC composite material comprising the following components in parts by weight:

[0007] 90-110 parts PC resin, 14-45 parts ASA resin, and 0.5-12 parts SAN resin;

[0008] The weight-average molecular weight of the ASA resin is 100,000 to 200,000, and the acrylonitrile content is ≥20%.

[0009] The weight-average molecular weight of the SAN resin is 180,000 to 250,000.

[0010] PC resin itself possesses ideal processability and mechanical strength, along with good flowability. However, this also leads to PC composites being extremely prone to deformation and exhibiting poor dimensional stability. Furthermore, due to its inherently hydrolyzable and oxidizable nature, its weather resistance is also unsatisfactory. Addressing this technical challenge, the inventors of this invention employ ASA resin with specific molecular weights and acrylonitrile content for compounding. Unlike conventional PC / ASA alloy materials, this invention also incorporates a portion of SAN resin with specific molecular weights for compounding. In this resin system, ASA resin exhibits ideal elastic molecular crosslinking properties and lacks unstable groups such as double bonds. After compounding with SAN resin, the product's weather resistance and dimensional stability are significantly improved. Simultaneously, when the acrylonitrile content in the ASA resin reaches 20% or higher, the product's resistance to deformation is greatly enhanced without directly affecting its flowability, and the product's processing performance remains excellent.

[0011] Preferably, the weight parts of the ASA resin are one or any two of the following: 14 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, and 45 parts; and the weight parts of the SAN resin are one or any two of the following: 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 8 parts, 10 parts, and 12 parts.

[0012] Preferably, the mass ratio of the ASA resin to the SAN resin is 10:(0.5 to 1.5).

[0013] As mentioned above, ASA resin and SAN resin can effectively improve the dimensional stability and resistance to deformation of products to a certain extent, while also affecting the processing performance of products. When ASA resin and SAN resin are introduced into PC resin according to the above ratio, the overall performance of the product is optimal.

[0014] Preferably, the weight-average molecular weight of the ASA resin is 160,000 to 180,000.

[0015] The weight-average molecular weight of the ASA resin was confirmed by testing according to the GB / T 27843-2011 standard.

[0016] The molecular weight of ASA resin changes, as does its molecular chain length and the degree of crosslinking introduced into PC resin. When ASA resin with a molecular weight within the above range is selected, the prepared product has better overall performance.

[0017] Preferably, the acrylate content in the ASA resin is 20-60%.

[0018] Preferably, the acrylonitrile content of the ASA resin is 20-30%.

[0019] More preferably, the acrylonitrile content of the ASA resin is 20-25%.

[0020] More preferably, the acrylonitrile content of the ASA resin is 21-26.5%.

[0021] The acrylonitrile content of the ASA resin was confirmed by the following standard test method:

[0022] The product was melt-pressed on a hot press at a temperature of 260℃ and a pressure of 0.5MPa, and maintained at this temperature and pressure for 5 seconds. After the hot-pressed film cooled, a film approximately 0.1mm thick was obtained. The film was fixed on a sample holder and then placed in a sample chamber for transmission testing, with a scanning range of 4000–400cm. -1 The system performed 16 scans, with a resolution of 4 cm, a beam splitter (KBr), a detector (DTGS), and data processing using OMNIC 9.8 software.

[0023] Choose 2237cm -1 The CN stretching vibration absorption peak characterizes the acrylonitrile (AN) content, 770 cm⁻¹. -1 Using the Sty absorption peak of styrene as an internal standard reference, different proportions of this styrene standard were prepared, and the relative peak heights of the characteristic absorption peaks were calculated. The peak height ratio of the AN characteristic absorption peak to the Sty characteristic absorption peak was also calculated. A standard curve was established with the peak height ratio as the ordinate and the content of different components as the abscissa.

[0024] The linear regression equation for acrylonitrile is y = 0.561x + 0.002, with a correlation coefficient of 0.991.

[0025] The relative content of each component can be obtained through the standard curve, and then the relative percentage content of each component can be obtained by substituting it into the following formula:

[0026] An%=MAn / (MAn+MSty+MMMA)*100

[0027] The acrylonitrile content of the ASA resin is accurate to ±0.5%. The acrylonitrile content in the ASA resin affects the rigidity, toughness, and resistance to deformation of the product. When the acrylonitrile content of the ASA resin is preferably in the range of 20-25%, the product can achieve the best resistance to deformation and dimensional stability.

[0028] Preferably, the weight-average molecular weight of the SAN resin is 190,000 to 200,000.

[0029] The weight-average molecular weight of the SAN resin was confirmed by testing according to the GB / T 27843-2011 standard.

[0030] Similar to ASA resin, changes in the molecular weight of SAN also affect its performance; when it is preferably within the range mentioned above, its performance is optimal.

[0031] Preferably, the acrylonitrile content in the SAN resin is 10-50%.

[0032] Preferably, the PC resin is a bisphenol A type PC resin.

[0033] Preferably, the weight-average molecular weight of the PC resin is 15,000 to 25,000.

[0034] The weight-average molecular weight of the PC resin was confirmed by testing according to the GB / T 27843-2011 standard.

[0035] Preferably, in the PC composite material, the mass percentage of PC resin is ≥60wt%.

[0036] Preferably, the PC composite material further comprises 0.01 to 1 part flame retardant and 0.01 to 1 part antibacterial agent.

[0037] In the manufacture of products such as automotive parts, in order to broaden their application areas, those skilled in the art can introduce flame retardants and antibacterial agents to impart flame retardant and antibacterial properties to the products without affecting their processability, weather resistance, deformation resistance and dimensional stability.

[0038] More preferably, the polycarbonate composition may further include at least one of 0.01 to 1 part filler, 0.01 to 1 part antioxidant, 0.01 to 1 part toughening agent, and 0.01 to 1 part compatibilizer.

[0039] Based on the needs of actual products, those skilled in the art may also appropriately introduce some other functional components commonly used in PC / ASA alloy products without affecting product performance, such as fillers to improve rigidity, antioxidants to improve product oxidation resistance, and toughening agents to improve product toughness, etc.

[0040] Another object of the present invention is to provide a method for preparing the PC composite material, comprising the following steps:

[0041] After the components are mixed evenly, they are melt-extruded and granulated in a screw extruder to obtain the PC composite material.

[0042] The preparation method of the PC composite material described in this invention has simple operation steps and can achieve industrial-scale production.

[0043] Preferably, the temperature range of the screw extruder is set to 250–280°C, the screw speed is 300–600 r / min, and the screw length-to-diameter ratio is 48:1.

[0044] Another object of the present invention is to provide the application of the PC composite material in the manufacture of automotive parts.

[0045] Preferably, the automotive component is an air intake grille.

[0046] The PC composite material described in this invention has high machinability, a helix length of up to 470 or more, good dimensional stability, excellent resistance to deformation, and good weather resistance, making it very suitable for the manufacture of components such as air intake grilles that need to be used in humid and hot environments for a long time.

[0047] The beneficial effects of the present invention are that it provides a PC composite material and its preparation method. By introducing SAN resin and ASA resin of specific molecular weight into the matrix PC resin and specifically limiting the acrylonitrile content in the ASA resin, the product can not only ensure good weather resistance and deformation resistance, but also retain the easy processability of the PC resin itself. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the air intake grille sample to be tested in the deformation resistance test of Example 1 of the present invention. Detailed Implementation

[0049] To better illustrate the purpose, technical solution, and advantages of this invention, the invention will be further described below with reference to specific embodiments and comparative examples. The purpose of this description is to provide a detailed understanding of the invention, not to limit its scope. All other embodiments obtained by those skilled in the art without inventive effort are within the protection scope of this invention. Unless otherwise specified, the experimental reagents and instruments involved in the implementation of this invention are commonly used reagents and instruments.

[0050] Examples 1-17

[0051] An embodiment of the PC composite material and its preparation method described in this invention is shown in Table 1.

[0052] The preparation method of the PC composite material includes the following steps:

[0053] After all the components in the formula are mixed uniformly in a high-speed mixer, they are fed into a twin-screw extruder through the main feed port for melt blending extrusion and granulation to obtain the PC composite material.

[0054] During the melt blending extrusion of the components, the temperature zones of the twin-screw extruder are set as follows: Zone 1 250℃, Zone 2 260℃, Zone 3 260℃, Zone 4 260℃, Zone 5 270℃, Zone 6 270℃, Zone 7 270℃, Zone 8 280℃, Zone 9 280℃, Zone 10 280℃, Zone 11 270℃, and Zone 12 270℃. The screw speed is 400 rpm, and the screw length-to-diameter ratio is 48:1.

[0055] Comparative Examples 1-9

[0056] The only difference between each comparative example and the embodiment is the type and ratio of components, as shown in Table 2.

[0057] In the components described in each embodiment and comparative example,

[0058] The PC resin 1 is PC 1300 10NP produced by LG Chem, with a weight-average molecular weight of 20,000;

[0059] The PC resin 2 is PC FN1900 manufactured by Idemitsu Corporation of Japan, with a weight-average molecular weight of 19,000.

[0060] The ASA resin 1 is Luran S 757R produced by BASF in Germany, with a weight average molecular weight of 160,000 and an acrylonitrile content of 22.1%.

[0061] The ASA resin 2 is Luran S 796M produced by BASF in Germany, with a weight average molecular weight of 180,000 and an acrylonitrile content of 22.3%.

[0062] The ASA resin 3 is Luran S 777K produced by BASF in Germany, with a weight average molecular weight of 100,000 and an acrylonitrile content of 24.3%.

[0063] The ASA resin 4 is Luran S 778T produced by BASF in Germany, with a weight average molecular weight of 200,000 and an acrylonitrile content of 21.2%.

[0064] The ASA resin 5 is Luran S 797S produced by BASF in Germany, with a weight average molecular weight of 190,000 and an acrylonitrile content of 26.5%.

[0065] The ASA resin 6 is Luran S 757G produced by BASF in Germany, with a weight average molecular weight of 90,000 and an acrylonitrile content of 26.2%.

[0066] The ASA resin 7 is Luran S 776S produced by BASF in Germany, with a weight average molecular weight of 220,000 and an acrylonitrile content of 21.5%.

[0067] The ASA resin 8 is Luran S KR2859 produced by BASF in Germany, with a weight average molecular weight of 180,000 and an acrylonitrile content of 19.1%.

[0068] The SAN resin 1 is PN-137H produced by Chi Mei Corporation in Taiwan, China, with a weight-average molecular weight of 190,000.

[0069] The SAN resin 2 is PN-127 produced by Chi Mei Corporation in Taiwan, China, with a weight-average molecular weight of 200,000.

[0070] The SAN resin 3 is PN-106 produced by Chi Mei Corporation in Taiwan, China, with a weight-average molecular weight of 180,000.

[0071] The SAN resin 4 is PN-138H produced by Chi Mei Corporation in Taiwan, China, with a weight-average molecular weight of 250,000.

[0072] The SAN resin 5 is PN-107L125 produced by Chi Mei Corporation in Taiwan, China, with a weight-average molecular weight of 100,000.

[0073] The SAN resin 6 is PN-117H L150 produced by Chi Mei Corporation in Taiwan, China, with a weight-average molecular weight of 270,000.

[0074] The weather-resistant additive is LP-1 PMMA produced by Asahi Kasei, with a weight-average molecular weight of 25,000.

[0075] Unless otherwise specified, all components and raw materials used in the embodiments and comparative examples of this invention are commercially available, and the same type of components and raw materials are used in each parallel experiment.

[0076] Table 1

[0077]

[0078] Table 2

[0079] Components by weight Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 PC resin 1 100 100 100 100 100 100 100 ASA resin 1 30 30 30 30 ASA resin 6 30 ASA resin 7 30 ASA resin 8 30 SAN resin 1 3 3 3 SAN resin 5 3 SAN resin 6 3 Weather-resistant additives 3

[0080] Example 1

[0081] To verify the performance of the PC composite material described in this invention, the products prepared in each embodiment and comparative example were subjected to the following performance tests, with the specific steps as follows:

[0082] (1) Deformation resistance test: Each sample was injection molded into shape as shown in the figure. Figure 1 The air intake grille with dimensions of 1455*935*192 shown was then placed in an electromagnetic vibration testing machine and vibrated for 30 minutes at a vibration frequency of 50Hz at -20℃ and 60℃ respectively. The change rate of the horizontal line dimension was recorded. If the change rate of dimension is ≤2mm, the sample is judged to be qualified in terms of deformation resistance; otherwise, it is unqualified.

[0083] (2) Dimensional stability test: The sample was injection molded into a 100*100*2mm test template, and the template length L0 was recorded. Then, it was kept at 80℃ for 24h, and the template length L1 was measured. The dimensional change rate was calculated using the formula (L1-L0) / L0×100%.

[0084] (3) Spiral length test: With a fixed injection temperature of 260℃, injection pressure of 50%, injection speed of 50%, holding time of 3s, cooling time of 5s, and mold temperature of 80℃, after 20 consecutive injections, the spiral length readings from the 15th to the 20th molds were recorded and the average value was calculated as the final result. Under the same test conditions, a longer spiral length indicates better injection molding processability.

[0085] (4) Weather resistance test: The sample was left to stand for 1000 hours at 85℃ and 85% relative humidity. The melt flow rate of the plastic particles before and after standing was tested according to ISO 1133-2011. The test conditions were 300℃ and 1.2KG. The change rate was recorded. The smaller the change rate, the better the weather resistance of the sample.

[0086] The test results are shown in Tables 3 and 4.

[0087] Table 3

[0088]

[0089] Table 4

[0090] Test Project Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Deformation resistance Unqualified Unqualified Unqualified Unqualified Unqualified Unqualified Unqualified Dimensional stability (%) 2.2 1.5 1.1 0.7 1.0 0.8 0.6 Helix length 480 540 501 520 497 513 463 Weather resistance (%) 16 10 14 28 20 16 17

[0091] As shown in Tables 3 and 4, the product of this invention has a spiral length of over 470 mm, good processability, and all products in each embodiment passed the deformation resistance test. In the dimensional stability test, the dimensional change rate was maintained at 0.6% or less, and in the weathering test, the melt flow rate change rate was maintained at 15% or less, demonstrating excellent overall performance. In contrast, the product of Comparative Example 1 is a PC / ASA alloy material without any additional additives. This product has unsatisfactory dimensional stability and poor weather resistance. Furthermore, Comparative Example 2 further introduced weathering additives used in existing processes to improve weather resistance. Although the weather resistance of this product was improved, its dimensional stability and deformation resistance were still not ideal, making it unsuitable for the manufacture of components such as air intake grilles. As can be seen from Examples 2, 6-9, and Comparative Examples 3-5, even if those skilled in the art prepare PC / ASA / SAN alloy products, the desired effect cannot be achieved if the type of ASA resin is not properly selected. Taking Comparative Examples 3 and 4 as examples, the molecular weight of the ASA resin used in these two products is too large or too small, and the product's resistance to deformation and weathering cannot meet the standards. In contrast, the performance of the products in Examples 2 and 6-9 is qualified, and the molecular weight of the products in Examples 2 and 6 is preferably in the range of 160,000 to 180,000, resulting in better overall performance. On the other hand, the acrylonitrile content of the ASA resin in the product of Comparative Example 5 is less than 20%, and the product cannot achieve the expected dimensional stability. However, the acrylonitrile content of the ASA resin in the products of Examples 2 and 6-9 reaches more than 20%, so the product performance is qualified. Furthermore, a comparison between Examples 2, 6, and 9 shows that when the acrylonitrile content is in the range of 20-30%, the overall performance of the product is better.

[0092] Similarly, as can be seen from Examples 2, 10-12 and Comparative Examples 6-7, the selection of SAN resin requires careful consideration of molecular weight. When the molecular weight is too small or too large, the performance of the product is also difficult to achieve the expected results. It must be limited to the range of 180,000 to 250,000. When it is further preferred to be in the range of 190,000 to 200,000, the performance of the product is even better.

[0093] As can be seen from Examples 2 and 13-16, when the PC resin and ASA resin are constant, the best overall performance of the product is achieved when the ratio of ASA resin to SAN resin is 10:(0.5-1.5).

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A PC composite material, characterized in that, Includes the following components in parts by weight: 90-110 parts PC resin, 14-45 parts ASA resin, and 0.5-12 parts SAN resin; The weight-average molecular weight of the PC resin is 15,000 to 25,000. The weight-average molecular weight of the ASA resin is 100,000 to 200,000, and the acrylonitrile content is 20% to 30%. The weight-average molecular weight of the SAN resin is 180,000 to 250,000.

2. The PC composite material as described in claim 1, characterized in that, The mass ratio of ASA resin to SAN resin is 10:(0.5 to 1.5).

3. The PC composite material as described in claim 1, characterized in that, The weight-average molecular weight of the ASA resin is 150,000 to 180,000.

4. The PC composite material as described in claim 1, characterized in that, The weight-average molecular weight of the SAN resin is 190,000 to 200,000.

5. The method for preparing the PC composite material according to any one of claims 1 to 4, characterized in that, Includes the following steps: After the components are mixed evenly, they are melt-extruded and granulated in a screw extruder to obtain the PC composite material.

6. The use of the PC composite material as described in any one of claims 1 to 4 in the manufacture of automotive parts.

7. The application as described in claim 6, characterized in that, The automotive component in question is the air intake grille.

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